A motion transmission system in a bicycle comprises a chain extended between toothed wheels associated with the axle of the pedal cranks and with the hub of the rear wheel. When there is more than one toothed wheel at at least one between the axle of the pedal cranks and the hub of the rear wheel, and the motion transmission system is therefore equipped with a gearshift, a front derailleur and/or a rear derailleur is provided. In the case of an electronically servo-assisted gearshift, each derailleur comprises a chain guide element, also known as cage plate, which is movable to move the chain between the toothed wheels in order to vary the transmission ratio, and an electromechanical actuator to move the chain guide element. Typically, the actuator in turn comprises a motor, typically an electric motor, coupled with the chain guide element by means of a linkage such as an articulated parallelogram, a rack system or a worm screw system, as well as a position, speed and/or acceleration sensor of the rotor or of any mobile part downstream of the rotor, up to the chain guide element itself. It is worth emphasising that slightly different terminology from that used in this context is also in use.
A control electronics varies the transmission ratio based on commands manually entered by the cyclist by mean of suitable control devices, for example a lever and/or buttons and/or based on automatically entered commands or, as far as the invention is concerned, semi-automatically entered commands. In case of automatically or semi-automatically entered commands, the control electronics establishes—typically based on the outputs of sensors of the travel parameters—such as the travel speed, the rotation speed of the pedal cranks, the slope of the travel ground, the heart rate of the cyclist and similar—when it is suitable to change transmission ratio and automatically generates signals requesting movement of the derailleur (automatic operation) or performs a supervision/integration of the cyclist's requests, preventing them, bypassing them, delaying them and/or integrating them with automatically generated requests, or vice-versa proposing such requests to the cyclist that in any case has the option of bypassing them (semi-automatic operation).
It is well known that for bicycles intended for racing there is a constant search for solutions to improve performance. In particular, for bicycles intended for speed races, such as typically time trials, a good aerodynamic configuration of all of the bicycle components is particularly important. Moreover, a factor for improving performance is considered to be the efficiency of all of the controls, but also how safe and easy they are to actuate, in that the cyclist is able to concentrate on the physical effort without obstacles due to difficulties in actuating the controls.
Recently, specialised handlebars for speed races have become popular, which have two or four bars or ends facing markedly forwards, which allow the cyclist to maintain a position of the torso greatly inclined forwards, which is aerodynamically efficient.
With these handlebars, specific control devices have also become well-established, both for the brakes and for the gearshift; these devices are commonly called bar-end devices since they are housed right at the ends of the handlebars, so that the cyclist can actuate them easily without having to change his position.
As mentioned before, manual bicycle gearshift control devices of the bar-end types comprise lever control devices and button control devices.
A lever-operated manual control device of the bar-end type comprises an assembly portion suitable for being mounted at the end of a handlebars facing forwards in the travel direction of the bicycle, a control lever projecting forwards from the assembly portion of the manual control device in the travel direction of the bicycle and means for imparting at least one control signal, typically comprising a pair of switches actuated by the lever. The control signals are transmitted to an electronic gearshifting control unit through a multiconductor cable.
Typically, the lever is angularly mobile with respect to the assembly portion between an intermediate neutral position, in which no gearshifting is commanded, and two operative positions, typically a raised operative position, in which an upward gearshifting is commanded, i.e. a movement of the chain, carried out by the rear or front derailleur, respectively, onto a toothed wheel of greater diameter with respect to the one currently engaged by the chain, and a lowered operative position, in which a downward gearshifting is commanded, i.e. a movement of the chain, carried out by the rear or front derailleur, respectively, onto a toothed wheel of smaller diameter with respect to the one currently engaged by the chain.
A button-operated manual control device of the bar-end type comprises an assembly portion suitable for being mounted at the end of the handlebars, a pair of buttons projecting from the assembly portion and means for imparting an electrical control signal, typically comprising a pair of switches actuated by the buttons. Also in this case, signals are transmitted to an electronic gearshifting control unit through a multiconductor cable. In particular, by acting on the upper button, the cyclist commands an upward gearshifting and by acting on the side button he commands a downward gearshifting.
It is also possible to use the lever/button to impart a command to change a transmission ratio, the electronic control unit providing for transforming the command into a gearshifting command of the rear and/or front derailleur.
Both with the lever-operated manual control device and with the button-operated manual control device, the electronic gearshifting control unit comprises an interface, in electrical connection with the switches of the control devices mounted on the right and left of the handlebars, and a power system in electrical connection with the interface. The interface is suitable for receiving, through the multiconductor cable, upward and downward gearshifting control signals imparted by the switches of the pair of gearshift control devices and for transmitting them to the power system that, as a function of the gearshifting control signal received, actuates the respective actuator of the rear and/or front wheel, so as to move the motion transmission chain on the toothed wheels associated with the axle of the pedal cranks and with the hub of the rear wheel, so as to establish the transmission ratio selected by the cyclist, thus carrying out the gearshifting.
Both with the lever-operated manual control device and with the button-operated manual control device it is possible to provide other switches, for example a switch for a so-called MODE command, operated by a lever or by a button, for selecting an operating mode selected from normal travel, setting of gearshift parameters etc., and/or a switch for a so-called SET command, for selecting a value of the selected gearshift parameters.
In the typical configuration (hereafter “standard”) of a handlebars equipped with manual bicycle gearshift control devices of the bar-end type, the right device controls upward and downward gearshifting in the rear derailleur, whereas the left device controls upward and downward gearshifting in the front derailleur.
If a cyclist wishes to perform an upward gearshifting of the rear derailleur, he must lift the lever, or correspondingly press the upper button, of the manual gearshift control device mounted on the right of the handlebars, thus activating the respective switch. An upward gearshifting signal of the rear derailleur is thus generated, which is transmitted, through the multi-conductor cable, to the interface and from this to the power system of the electronic gearshifting control unit. The power system, in turn, actuates the actuator of the rear derailleur so as to move the chain onto a toothed wheel of greater diameter among the toothed wheels associated with the hub of the rear wheel.
Differently, if a cyclist wishes to perform a downward gearshifting of the rear derailleur, he must lower the lever, or correspondingly press the side button, of the manual gearshift control device mounted on the right of the handlebars, thus activating the respective switch. A downward gearshifting signal of the rear derailleur is thus generated, which is transmitted, through the multi-conductor cable, to the interface and from this to the power system of the electronic gearshifting control unit. The power system, in turn, actuates the actuator of the rear derailleur so as to move the chain onto a toothed wheel of smaller diameter.
Similarly, if a cyclist wishes to perform an upward gearshifting of the front derailleur, he must lift the lever, or correspondingly press the upper button, of the manual gearshift control device mounted on the left of the handlebars, thus activating the respective switch. An upward gearshifting signal of the front derailleur is thus generated, which is transmitted, through the multi-conductor cable, to the interface and from this to the power system of the electronic gearshifting control unit. The power system, in turn, actuates the actuator of the front derailleur so as to move the chain onto a toothed wheel of greater diameter among the toothed wheels associated with the axle of the pedal cranks.
Finally, if a cyclist wishes to perform a downward gearshifting of the front derailleur, he must lower the lever, or correspondingly press the side button, of the manual gearshift control device mounted on the left of the handlebars, thus activating the respective switch. A downward gearshifting signal of the front derailleur is thus generated, which is transmitted, through the multi-conductor cable, to the interface and from this to the power system of the electronic gearshifting control unit. The power system, in turn, actuates the actuator of the front derailleur so as to move the chain onto a toothed wheel of smaller diameter.
The Applicant has now realised that a cyclist could wish to have inverted gearshifting commands, due to personal preference, due to physical characteristics, for example left or right-handed cyclist, and/or due to particular requirements, for example associated with riding style, in particular with the aerodynamic position taken up during a time trial in the case of gearshift control devices of the bar-end type.
More specifically, a cyclist could wish to command upward gearshifting by lowering, instead of lifting, the lever, or by pressing the side button, instead of the upper button, of the manual gearshift control device and to command downward gearshifting by lifting, instead of lowering, the lever, or by pressing the upper button, instead of the side button, of the manual gearshift control device.
Furthermore, the cyclist could wish to use the manual gearshift control device, operated by a lever or buttons, mounted on the right of the handlebars to command upward gearshifting both of the front derailleur and of the rear derailleur and to use the manual gearshift control device, operated by a lever or buttons, mounted on the left of the handlebars to command downward gearshifting both of the front derailleur and of the rear derailleur, or vice-versa.
Furthermore, other configurations of inversion or variation of the controls may be desirable, for example inversions between the upward and/or downward gearshifting controls and the MODE and/or SET commands defined above.
Also in the case of a control device not of the bar-end type, the cyclist could have a reason to wish to vary the gearshifting commands imparted with each lever/button.
The technical problem forming the basis of the present invention is, therefore, to allow the cyclist to personalise the generation, by means of manual control devices, of upward and downward gearshifting controls of the rear and/or front derailleur of the bicycle based on his preferences and/or needs, thus ensuring a high versatility in use of the control devices themselves.